Download or read book Improving the Monitoring Verification and Accounting of CO sub 2 Sequestered in Geologic Systems with Multicomponent Seismic Technology and Rock Physics Modeling written by and published by . This book was released on 2012 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Research done in this study showed that P-SV seismic data provide better spatial resolution of geologic targets at our Appalachian Basin study area than do P-P data. This finding is important because the latter data (P-P) are the principal seismic data used to evaluate rock systems considered for CO2 sequestration. The increase in P-SV1 resolution over P-P resolution was particularly significant, with P-SV1 wavelengths being approximately 40-percent shorter than P-P wavelengths. CO2 sequestration projects across the Appalachian Basin should take advantage of the increased resolution provided by converted-shear seismic modes relative to P-wave seismic data. In addition to S-wave data providing better resolution of geologic targets, we found S-wave images described reservoir heterogeneities that P-P data could not see. Specifically, a channel-like anomaly was imaged in a key porous sandstone interval by P-SV1 data, and no indication of the feature existed in P-P data. If any stratigraphic unit is considered for CO2 storage purposes, it is important to know all heterogeneities internal to the unit to understand reservoir compartmentalization. We conclude it is essential that multicomponent seismic data be used to evaluate all potential reservoir targets whenever a CO2 storage effort is considered, particularly when sequestration efforts are initiated in the Appalachian Basin. Significant differences were observed between P-wave sequences and S- wave sequences in data windows corresponding to the Oriskany Sandstone, a popular unit considered for CO2 sequestration. This example demonstrates that S-wave sequences and facies often differ from P-wave sequences and facies and is a principle we have observed in every multicomponent seismic interpretation our research laboratory has done. As a result, we now emphasis elastic wavefield seismic stratigraphy in our reservoir characterization studies, which is a science based on the concept that the same weight must be given to S-wave sequences and facies as is given to P-wave sequences and facies. This philosophy differs from the standard practice of depending on only conventional P-wave seismic stratigraphy to characterize reservoir units. The fundamental physics of elastic wavefield seismic stratigraphy is that S- wave modes sense different sequences and facies across some intervals than does a P-wave mode because S-wave displacement vectors are orthogonal to P- wave displacement vectors and thus react to a different rock fabric than do P waves. Although P and S images are different, both images can still be correct in terms of the rock fabric information they reveal.

Download or read book Multi Sensor Data Assimilation for Geological Carbon Storage Monitoring Design written by Shams Joon and published by . This book was released on 2022 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Geological carbon storage (GCS) is a climate change mitigation strategy that provides an innovative solution to offset the rising atmospheric CO2 concentrations. This process involves the injection of CO2 into underground geological formations where it is permanently trapped, thereby avoiding CO2 to be emitted into the atmosphere. The tax credit for CO2 sequestration (IRC Code: 45Q) has incentivized the feasibility of such operations and GCS is gaining substantial investment interest. The potential for CO2 to leak out and negatively impact the overlying environment is a primary concern for such operations and has motivated the development of risk-based monitoring, verification, and accounting (MVA) protocols around the world for Class II and Class VI wells. Fluid flow models are effective tools to simulate complex physical processes such as CO2 sequestration at a storage site. The accuracy of these models relies on multiple model parameters and state variables that are calibrated to reproduce the changing reservoir state. Geophysical monitoring data from multiple sources are used to further calibrate reservoir simulations and improve model accuracy. However, both the reservoir model and geophysical measurements produce uncertain predictions due to the underlying process and measurement errors. Monitoring tools can be evaluated based on their sensitivity, spatiotemporal coverage, cost, and regulatory requirements. Wellbore sensors, such as pressure gauges, provide high temporal sampling of the subsurface but are spatially limited to around the wellbore. In contrast, surface seismics can survey large volumes of the reservoir with a coarse spatial resolution and are costly which limits how frequently they can be conducted. Furthermore, using these types of geophysical monitoring tools to estimate changes in petrophysical properties is always subject to uncertainty due to inevitable ambiguities incurred during data acquisition, processing, and interpretation. Combining multiple sources of measurements can help reduce prediction uncertainty; however, quantifying the improvement afforded by such composite systems can be a challenging task when the true reservoir characteristics are unknown. Quantifying the reduction in prediction error from different monitoring tools and combinations of monitoring tools can also be useful to evaluate the efficacy of a proposed monitoring design. From a monitoring design perspective, this research validates the applicability of combining seismic attributes derived from full-waveform inversion of continuous active-source seismic monitoring (CASSM) data with pressure-based monitoring measurements to improve model state predictions. The improvement afforded by combining these two different types of measurements is quantified by computing the reduction in prediction error in an ensemble-based data assimilation environment. The first goal of this research is to develop and test out an ensemble-based data assimilation framework that takes advantage of rock physics models and combines numerical simulations with geophysical observations to predict subsurface changes at GCS sites. This proposed joint seismic-pressure-petrophysical data assimilation framework uses continuous geophysical measurements, in the form of seismic velocity (Vp) and seismic attenuation quality factor (Qp) along with wellbore pressure monitoring data (Pwf), to predict changes in the reservoir model state which is represented by CO2 saturation and reservoir pressure distributions. One of the challenges of using seismic data is the non-unique relationship between CO2 fluid properties and seismic attributes which introduces ambiguity (multiple solutions) during inversion. Rock physics models can be used to forward model seismic attributes but due to the highly non-linear nature of these models and the multidimensionality of reservoir rock and fluid properties, standard linear models are rendered unusable for inversion purposes. Combining different types of measurements (seismic with pressure) helps further constrain this non-uniqueness and improves the forward-modeled estimates. These multi-sensor measurements are assimilated using an ensemble Kalman filter (EnKF) which propagates the model state and uncertainty forward using an ensemble of reservoir realization and relies on ensemble-based sample statistics of the model state and measurement error to calibrate estimates when new measurements are made available. One of the novelties of this workflow is that the forward operator of the EnKF is replaced with rock physics models (RPMs). The choice of rock physics model depends on the geological context, the rock and fluid properties, operational parameters of the seismic survey, and available seismic attributes. I use one particular RPM i.e., White's patchy gas saturation model that we use for demonstration purposes, but one could use this general framework to employ any one of a variety of RPMs. I conduct a series of observation system simulation experiments (OSSEs) to demonstrate the effectiveness of this joint data assimilation framework by evaluating different monitoring tools and combination of monitoring tools on three different models. The OSSEs are first conducted on a lab-scale "sandbox" model before being tested on field-scale reservoir models like the Frio II brine pilot, near Houston, Texas and the Cranfield Site in Mississippi. In general, including seismic attributes improves the prediction estimate of CO2 saturation while Pwf measurements improve pressure prediction results by calibrating the well constraints and improving model state forecasts. Jointly assimilating both seismic and pressure data produces the greatest reduction in prediction error and the high temporal resolution afforded by continuous seismic measurements allows for shorter assimilation windows. Reducing the assimilation frequency increases the prediction error which is observed when CO2 injection is halted and the post-injection assimilation time window is increased. This improvement afforded by jointly assimilating multi-sensor observations is consistently observed in all three synthetic case studies even when different data assimilation parameters are varied such as type, ensemble size, assimilation frequency etc. After successfully implementing the multi-sensor, rock physics-based data assimilation framework in an OSSE environment, I integrate the framework with full-waveform inversion (FWI) results from the CASSM dataset at Frio II. In this work, the CASSM-derived FWI seismic attributes and wellbore pressure monitoring data are jointly assimilated to predict CO2 plume movement and reservoir pressure changes over a 5-day injection period. A comprehensive comparison of using a multi-sensor approach as compared to just wellbore pressure sensors is carried out to conclude that the error reduction afforded by using multiple sensors is valuable both from a perspective of risk as well as cost. Lastly, the multi-sensor, rock physics-based data assimilation framework is reconfigured for additional operational applications at GCS sites like observation targeting. In particular, this modified workflow takes advantage of ensemble-based sensitivity analysis to evaluate how changing the placement location of monitoring wells influences the prediction uncertainty of model state variables. Furthermore, by evaluating the efficacy of pre-existing and/or limited monitoring tools and designs, one can identify regions of the reservoir with highest uncertainty and subsequently find optimal locations for drilling new monitoring wells. A series of OSSEs of the Frio II reservoir model are used to demonstrate the applicability of this observation targeting approach.

Download or read book Training Toward Advanced 3D Seismic Methods for CO2 Monitoring Verification and Accounting written by and published by . This book was released on 2012 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The objective of our work is graduate and undergraduate student training related to improved 3D seismic technology that addresses key challenges related to monitoring movement and containment of CO2, specifically better quantification and sensitivity for mapping of caprock integrity, fractures, and other potential leakage pathways. We utilize data and results developed through previous DOE-funded CO2 characterization project (DE-FG26-06NT42734) at the Dickman Field of Ness County, KS. Dickman is a type locality for the geology that will be encountered for CO2 sequestration projects from northern Oklahoma across the U.S. midcontinent to Indiana and Illinois. Since its discovery in 1962, the Dickman Field has produced about 1.7 million barrels of oil from porous Mississippian carbonates with a small structural closure at about 4400 ft drilling depth. Project data includes 3.3 square miles of 3D seismic data, 142 wells, with log, some core, and oil/water production data available. Only two wells penetrate the deep saline aquifer. In a previous DOE-funded project, geological and seismic data were integrated to create a geological property model and a flow simulation grid. We believe that sequestration of CO2 will largely occur in areas of relatively flat geology and simple near surface, similar to Dickman. The challenge is not complex geology, but development of improved, lower-cost methods for detecting natural fractures and subtle faults. Our project used numerical simulation to test methods of gathering multicomponent, full azimuth data ideal for this purpose. Our specific objectives were to apply advanced seismic methods to aide in quantifying reservoir properties and lateral continuity of CO2 sequestration targets. The purpose of the current project is graduate and undergraduate student training related to improved 3D seismic technology that addresses key challenges related to monitoring movement and containment of CO2, specifically better quantification and sensitivity for mapping of caprock integrity, fractures, and other potential leakage pathways. Specifically, our focus is fundamental research on (1) innovative narrow-band seismic data decomposition and interpretation, and (2) numerical simulation of advanced seismic data (multi-component, high density, full azimuth data) ideal for mapping of cap rock integrity and potential leakage pathways.

Download or read book Microseismic Monitoring and Geomechanical Modelling of CO2 Storage in Subsurface Reservoirs written by James P. Verdon and published by Springer Science & Business Media. This book was released on 2012-01-11 with total page 193 pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis presents an impressive summary of the potential to use passive seismic methods to monitor the sequestration of anthropogenic CO2 in geologic reservoirs. It brings together innovative research in two distinct areas – seismology and geomechanics – and involves both data analysis and numerical modelling. The data come from the Weyburn-Midale project, which is currently the largest Carbon Capture and Storage (CCS) project in the world. James Verdon’s results show how passive seismic monitoring can be used as an early warning system for fault reactivation and top seal failure, which may lead to the escape of CO2 at the surface.

Download or read book Geophysics and Geosequestration written by Thomas L. Davis and published by Cambridge University Press. This book was released on 2019-05-09 with total page 391 pages. Available in PDF, EPUB and Kindle. Book excerpt: An overview of the geophysical techniques and analysis methods for monitoring subsurface carbon dioxide storage for researchers and industry practitioners.

Download or read book Near surface Monitoring Strategies for Geologic Carbon Dioxide Storage Verification written by Curtis M. Oldenburg and published by . This book was released on 2003 with total page 54 pages. Available in PDF, EPUB and Kindle. Book excerpt: Geologic carbon sequestration is the capture of anthropogenic carbon dioxide (CO{sub 2}) and its storage in deep geologic formations. Geologic CO{sub 2} storage verification will be needed to ensure that CO{sub 2} is not leaking from the intended storage formation and seeping out of the ground. Because the ultimate failure of geologic CO{sub 2} storage occurs when CO{sub 2} seeps out of the ground into the atmospheric surface layer, and because elevated concentrations of CO{sub 2} near the ground surface can cause health, safety, and environmental risks, monitoring will need to be carried out in the near-surface environment. The detection of a CO{sub 2} leakage or seepage signal (LOSS) in the near-surface environment is challenging because there are large natural variations in CO{sub 2} concentrations and fluxes arising from soil, plant, and subsurface processes. The term leakage refers to CO{sub 2} migration away from the intended storage site, while seepage is defined as CO{sub 2} passing from one medium to another, for example across the ground surface. The flow and transport of CO{sub 2} at high concentrations in the near-surface environment will be controlled by its high density, low viscosity, and high solubility in water relative to air. Numerical simulations of leakage and seepage show that CO{sub 2} concentrations can reach very high levels in the shallow subsurface even for relatively modest CO{sub 2} leakage fluxes. However, once CO{sub 2} seeps out of the ground into the atmospheric surface layer, surface winds are effective at dispersing CO{sub 2} seepage. In natural ecological systems with no CO{sub 2} LOSS, near-surface CO{sub 2} fluxes and concentrations are controlled by CO{sub 2} uptake by photosynthesis, and production by root respiration, organic carbon biodegradation in soil, deep outgassing of CO{sub 2}, and by exchange of CO{sub 2} with the atmosphere. Existing technologies available for monitoring CO{sub 2} in the near-surface environment include (1) the infrared gas analyzer (IRGA) for measuring point concentrations using IR absorption by the CO{sub 2} molecule, (2) the accumulation chamber (AC) method for measuring soil CO{sub 2} fluxes at discrete points, (3) the eddy correlation (EC) tower that measures net flux over a given area, and (4) light distancing and ranging (LIDAR) that can measure CO{sub 2} concentrations over an integrated path. Novel technologies that could potentially be useful for CO{sub 2} concentration and flux measurement include hyperspectral remote sensing of vegetative stress as an indication of elevated CO{sub 2} concentrations, tunable lasers for long distance integrated concentration measurements, microelectronic mechanical systems (MEMS) that can be dispersed to make widespread point measurements, and trained animals such as dogs as used for landmine detection.

Download or read book Investigation of Novel Geophysical Techniques for Monitoring CO2 Movement During Sequestration written by Erika Gasperikova and published by . This book was released on 2003 with total page 94 pages. Available in PDF, EPUB and Kindle. Book excerpt: Cost effective monitoring of reservoir fluid movement during CO{sub 2} sequestration is a necessary part of a practical geologic sequestration strategy. Current petroleum industry seismic techniques are well developed for monitoring production in petroleum reservoirs. The cost of time-lapse seismic monitoring can be born because the cost to benefit ratio is small in the production of profit making hydrocarbon. However, the cost of seismic monitoring techniques is more difficult to justify in an environment of sequestration where the process produces no direct profit. For this reasons other geophysical techniques, which might provide sufficient monitoring resolution at a significantly lower cost, need to be considered. In order to evaluate alternative geophysical monitoring techniques we have undertaken a series of numerical simulations of CO{sub 2} sequestration scenarios. These scenarios have included existing projects (Sleipner in the North Sea), future planned projects (GeoSeq Liberty test in South Texas and Schrader Bluff in Alaska) as well as hypothetical models based on generic geologic settings potentially attractive for CO{sub 2} sequestration. In addition, we have done considerable work on geophysical monitoring of CO{sub 2} injection into existing oil and gas fields, including a model study of the Weyburn CO{sub 2} project in Canada and the Chevron Lost Hills CO{sub 2} pilot in Southern California (Hoversten et al. 2003). Although we are specifically interested in considering ''novel'' geophysical techniques for monitoring we have chosen to include more traditional seismic techniques as a bench mark so that any quantitative results derived for non-seismic techniques can be directly compared to the industry standard seismic results. This approach will put all of our finding for ''novel'' techniques in the context of the seismic method and allow a quantitative analysis of the cost/benefit ratios of the newly considered methods compared to the traditional, more expensive, seismic technique. The Schrader Bluff model was chosen as a numerical test bed for quantitative comparison of the spatial resolution of various geophysical techniques being considered for CO{sub 2} sequestration monitoring. We began with a three dimensional flow simulation model provided by BP Alaska of the reservoir and developed a detailed rock-properties model from log data that provides the link between the reservoir parameters (porosity, pressure, saturations, etc.) and the geophysical parameters (velocity, density, electrical resistivity). The rock properties model was used to produce geophysical models from the flow simulations.

Download or read book WEST COAST REGIONAL CARBON SEQUESTRATION PARTNERSHIP REPORT ON GEOPHYSICAL TECHNIQUES FOR MONITORING CO2 MOVEMENT DURING SEQUESTRATION written by Erika Gasperikova and published by . This book was released on 2005 with total page 60 pages. Available in PDF, EPUB and Kindle. Book excerpt: The relative merits of the seismic, gravity, and electromagnetic (EM) geophysical techniques are examined as monitoring tools for geologic sequestration of CO{sub 2}. This work does not represent an exhaustive study, but rather demonstrates the capabilities of a number of geophysical techniques on two synthetic modeling scenarios. The first scenario represents combined CO{sub 2} enhance oil recovery (EOR) and sequestration in a producing oil field, the Schrader Bluff field on the north slope of Alaska, USA. EOR/sequestration projects in general and Schrader Bluff in particular represent relatively thin injection intervals with multiple fluid components (oil, hydrocarbon gas, brine, and CO{sub 2}). This model represents the most difficult end member of a complex spectrum of possible sequestration scenarios. The time-lapse performance of seismic, gravity, and EM techniques are considered for the Schrader Bluff model. The second scenario is a gas field that in general resembles conditions of Rio Vista reservoir in the Sacramento Basin of California. Surface gravity, and seismic measurements are considered for this model.

Download or read book Integrated Reflection Seismic Monitoring and Reservoir Modeling for Geologic CO2 Sequestration written by and published by . This book was released on 2011 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The US DOE/NETL CCS MVA program funded a project with Fusion Petroleum Technologies Inc. (now SIGMA) to model the proof of concept of using sparse seismic data in the monitoring of CO2 injected into saline aquifers. The goal of the project was to develop and demonstrate an active source reflection seismic imaging strategy based on deployment of spatially sparse surface seismic arrays. The primary objective was to test the feasibility of sparse seismic array systems to monitor the CO2 plume migration injected into deep saline aquifers. The USDOE/RMOTC Teapot Dome (Wyoming) 3D seismic and reservoir data targeting the Crow Mountain formation was used as a realistic proxy to evaluate the feasibility of the proposed methodology. Though the RMOTC field has been well studied, the Crow Mountain as a saline aquifer has not been studied previously as a CO2 sequestration (storage) candidate reservoir. A full reprocessing of the seismic data from field tapes that included prestack time migration (PSTM) followed by prestack depth migration (PSDM) was performed. A baseline reservoir model was generated from the new imaging results that characterized the faults and horizon surfaces of the Crow Mountain reservoir. The 3D interpretation was integrated with the petrophysical data from available wells and incorporated into a geocellular model. The reservoir structure used in the geocellular model was developed using advanced inversion technologies including Fusion's ThinMAN{trademark} broadband spectral inversion. Seal failure risk was assessed using Fusion's proprietary GEOPRESS{trademark} pore pressure and fracture pressure prediction technology. CO2 injection was simulated into the Crow Mountain with a commercial reservoir simulator. Approximately 1.2MM tons of CO2 was simulated to be injected into the Crow Mountain reservoir over 30 years and subsequently let 'soak' in the reservoir for 970 years. The relatively small plume developed from this injection was observed migrating due to gravity to the apexes of the double anticline in the Crow Mountain reservoir of the Teapot dome. Four models were generated from the reservoir simulation task of the project which included three saturation models representing snapshots at different times during and after simulated CO2 injection and a fully saturated CO2 fluid substitution model. The saturation models were used along with a Gassmann fluid substitution model for CO2 to perform fluid volumetric substitution in the Crow Mountain formation. The fluid substitution resulted in a velocity and density model for the 3D volume at each saturation condition that was used to generate a synthetic seismic survey. FPTI's (Fusion Petroleum Technologies Inc.) proprietary SeisModelPRO{trademark} full acoustic wave equation software was used to simulate acquisition of a 3D seismic survey on the four models over a subset of the field area. The simulated acquisition area included the injection wells and the majority of the simulated plume area.

Download or read book Geophysical Techniques for Monitoring CO2 Movement During Sequestration written by Erika Gasperikova and published by . This book was released on 2005 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The relative merits of the seismic, gravity, and electromagnetic (EM) geophysical techniques are examined as monitoring tools for geologic sequestration of carbon dioxide (CO{sub 2}). This work does not represent an exhaustive study, but rather demonstrates the capabilities of a number of geophysical techniques for two synthetic modeling scenarios. The first scenario represents combined CO{sub 2} enhanced oil recovery (EOR) and sequestration in a producing oil field, the Schrader Bluff field on the north slope of Alaska, USA. EOR/sequestration projects in general and Schrader Bluff in particular represent relatively thin injection intervals with multiple fluid components (oil, hydrocarbon gas, brine, and CO{sub 2}). This model represents the most difficult end member of a complex spectrum of possible sequestration scenarios. The time-lapse performance of seismic, gravity, and EM techniques are considered for the Schrader Bluff model. The second scenario is a gas field that in general resembles conditions of Rio Vista reservoir in the Sacramento Basin of California. Surface gravity, and seismic measurements are considered for this model.

Download or read book Double Difference Tomography for Sequestration MVA monitoring Verification and Accounting written by and published by . This book was released on 2012 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Analysis of synthetic data was performed to determine the most cost-effective tomographic monitoring system for a geologic carbon sequestration injection site. Double-difference tomographic inversion was performed on 125 synthetic data sets: five stages of CO2 plume growth, five seismic event regions, and five geophone arrays. Each resulting velocity model was compared quantitatively to its respective synthetic velocity model to determine an accuracy value. The results were examined to determine a relationship between cost and accuracy in monitoring, verification, and accounting applications using double-difference tomography. The geophone arrays with widely-varying geophone locations, both laterally and vertically, performed best. Additionally, double difference seismic tomography was performed using travel time data from a carbon sequestration site at the Aneth oil field in southeast Utah as part of a Department of Energy initiative on monitoring, verification, and accounting (MVA) of sequestered CO2. A total of 1,211 seismic events were recorded from a borehole array consisting of 22 geophones. Artificial velocity models were created to determine the ease with which different CO2 plume locations and sizes can be detected. Most likely because of the poor geophone arrangement, a low velocity zone in the Desert Creek reservoir can only be detected when regions of test site containing the highest ray path coverage are considered. MVA accuracy and precision may be improved through the use of a receiver array that provides more comprehensive ray path coverage.

Download or read book Quantitative Monitoring of CO2 Injection at Sleipner Using Seismic Full Waveform Inversion in the Time Lapse Mode and Rock Physics Modeling written by Manuel Peter Queisser and published by . This book was released on 2011 with total page 269 pages. Available in PDF, EPUB and Kindle. Book excerpt: Carbon capture and sequestration is a technology to achieve a considerable deceleration of CO2 emission promptly. Since 1996 one of the largest CO2 storage projects is taking place at Sleipner in the Norwegian North Sea. In order to monitor injected CO2, time lapse surface seismic monitoring surveys have been carried out. Estimating subsurface parameters from the Sleipner seismic data is a challenging problem due to the specific geology of the storage reservoir, which is further complicated by injected CO2. Most seismic imaging methods enable only qualitative insights into the subsurface. Full waveform inversion is well known in the seismic community but not well established yet. Presented results are mostly of demonstrative character. Applying full waveform inversion as an actual tool to a complex problem such as Sleipner is novel. Motivated by the need for a quantitative seismic monitoring of the injected CO2, I have applied 2D seismic full waveform inversion to seismic data sets from Sleipner from 1994 (baseline), 1999 and 2006 along three seismic lines to infer subsurface parameters and parameter changes in the storage reservoir. The P-wave velocity is the major parameter, as it is the most sensitive to CO2 injection. An energy preconditioning of the gradient has been implemented. The usual source wavelet calibration did not prove to be reliable. An alternative source calibration has been successfully applied. By comparing seismic images with inversion results, I found that using seismic images to locate CO2 accumulations in the subsurface may be misleading. The quantitative imaging approach using full waveform inversion resulted in a consistent evolution of the model parameter with time. Major reductions in Pwave velocity and hence the CO2 accumulations could be quantitatively imaged down to a resolution of 10 m. Observed travel time shifts due to CO2 injection are comparable to those derived from the inversion result. In order to estimate CO2 saturations, rock physical concepts have been combined and extended to arrive at a rock physical formulation of the subsurface at Sleipner. I used pseudo Monte Carlo rock physics modeling to assess the influence of lithologic heterogeneity on the CO2 saturations as well as to generate pseudo well logs to estimate confidence intervals of the inverted parameters. The rock physics modeling has been used to relate inverted parameters to CO2 saturations. The injected CO2 is buoyant. The highest CO2 saturations are in the upper half of the storage reservoir but not necessarily at the top. Non-uniqueness of the saturation maps associated with the density scenario has been assessed. As a result, the distribution of the maximum saturation values remains the same. The quantity of dissolved CO2 in the reservoir water is a key parameter from both a security and optimization point of view. A quantitative estimation of dissolved CO2 by seismic means has not been undertaken yet to our knowledge. Based on the seismic inversion result of a seismic line, I found that along the line at least 20% of the injected CO2 mass was dissolved in 2006, after 10 years of injection. Such a high value indicates enhanced solubility trapping, which is very advantageous for storage safety at Sleipner. The results of this work represent a further step towards ultimate goals of quantitative monitoring, such as the estimation of the injected CO2 in-situ volume.

Download or read book Monitoring Verification and Accounting of CO2 in Deep Geologic Formations written by and published by . This book was released on 2009 with total page 132 pages. Available in PDF, EPUB and Kindle. Book excerpt: The report was prepared by NETL with input from the seven Regional Carbon Sequestration Partnerships. Its main goals are to provide an overview of monitoring, verification, and accounting (MVA) techniques that are currently in use or are being developed, summarize the Energy Department's MVA research and development program, present information that can be used by regulatory organizations, project developers, and national and state policymakers to ensure the safety and efficacy of carbon storage projects. Reliable and cost-effective MVA techniques are critical to making geologic storage a safe, effective, and acceptable method for reducing greenhouse gas emissions. Additionally, MVA provides data that can be used to verify national inventories of greenhouse gases, assess reductions of greenhouse gas emissions at geologic sequestration sites, evaluate potential regional, national, and international greenhouse gas reduction goals.

Download or read book Multicomponent Seismic Monitoring of CO2 Gas Cloud in the Utsira Sand a Feasibility Study Saline Aquifer Co2 Storage Phase 2 SACS2 Work Area 5 Geophysics Feasibility of Multicomponent Seismic Acquisition written by E. Liu and published by . This book was released on 2001 with total page 41 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Integration of Prestack Waveform Inversion and Rock Physics Inversion for CO2 Reservoir Characterization written by Josianne L. Pafeng Tschuindjang and published by . This book was released on 2017 with total page 146 pages. Available in PDF, EPUB and Kindle. Book excerpt: This dissertation addresses a seismic reservoir characterization study and time-lapse feasibility of reservoir monitoring of carbon dioxide using seismic data, via rock physics models, global and local nonlinear inversions. It also aims to investigate the value of data integration, the relative impact of elastic and electrical rock physics model parameters on inverted petrophysical properties, and the feasibility of using resistivity data from time-lapse electromagnetic survey to monitor the displacement of carbon dioxide in the subsurface. This study focuses on the identification of target storage and sealing lithologies for a future carbon dioxide (CO2) monitoring project at the Rock Springs Uplift (RSU), Wyoming, USA. Seismic reservoir characterization aims to estimate reservoir rock and fluid properties such as porosity, fluid saturation, lithology, which are important properties for hydrocarbon exploration as well as carbon dioxide sequestration and monitoring projects. These petrophysical properties affect elastic attributes which in turn, affect the seismic response. Estimating reservoir properties therefore constitutes an inverse problem. Geophysical inverse problems are challenging because of the noise in recorded data, the nonlinearity of the inverse problem, the nonuniqueness of the solutions, etc. Depending upon the complexity of the problems, we can either use a local or a global optimization scheme to solve the specific problem. In this dissertation, we use a multilevel parallelization of a global prestack waveform inversion to three-dimensional seismic data with sparse well-information, to estimate subsurface elastic attributes like P-, S-wave velocity and density. This study contributes to the inversion of 3D large seismic data volume in an efficient computational time while providing high-resolution structural images of the subsurface compared to amplitude-variation-with-offset/angle (AVO/AVA) inversion. Following prestack waveform inversion, we use rock physics models to relate elastic attributes to reservoir properties and apply a local nonlinear least squares inversion scheme based on the trust-region algorithm, to invert elastic attributes for petrophysical properties like porosity and volumetric fractions of minerals. We apply this approach on well log data to validate the method, followed by applying it to the volumes of inverted elastic attributes obtained from prestack waveform inversion, to provide reservoir characterization away from the well. Because a carbon dioxide sequestration project is planned at the Rock Springs Uplift, we also investigate the feasibility of a time-lapse reservoir monitoring for the area using seismic data, by simulating the pressure and fluid effects on elastic velocities and synthetic seismograms. In the final part of this dissertation, we investigate the value of data integration by combining elastic and electrical attributes in a joint petrophysical inversion for reservoir rock and fluid properties. We illustrate the methodology using well log data sets from the Barents Sea and the Rock Springs Uplift, and show that the estimation of reservoir properties can be improved by combining multiple geophysical data. Despite the geological information we might have on a study area, there is often uncertainty in the choice of an adequate rock physics model and its input parameters not only at the well location, but also in areas with sparse well control. This study therefore helps understand the impact of such model parameters on inverted petrophysical properties and how it could affect reservoir interpretation. Next, we use a simple sharp interface model in order to provide a preliminary assessment of the extent of the CO2 plume, and thus address potential leakage risks. We also simulate the spatial distribution of CO2 after injection and compute corresponding resistivity datasets at different spatial resolutions, which we invert for water saturation. This synthetic study helps investigate the ability of monitoring the CO2 displacement using geophysical data.

Download or read book Improved Understanding of Geologic CO sub 2 Storage Processes Requires Risk driven Field Experiments written by and published by . This book was released on 2011 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The need for risk-driven field experiments for CO2 geologic storage processes to complement ongoing pilot-scale demonstrations is discussed. These risk-driven field experiments would be aimed at understanding the circumstances under which things can go wrong with a CO2 capture and storage (CCS) project and cause it to fail, as distinguished from accomplishing this end using demonstration and industrial scale sites. Such risk-driven tests would complement risk-assessment efforts that have already been carried out by providing opportunities to validate risk models. In addition to experimenting with high-risk scenarios, these controlled field experiments could help validate monitoring approaches to improve performance assessment and guide development of mitigation strategies.

Download or read book Monitoring Verification and Accounting of CO2 Stored in Deep Geologic Formations written by National Energy Technology Laboratory (U.S.) and published by . This book was released on 2009 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: